JP 2008096547 (O. Ito et al.; published Apr. 24, 2008) describes a display which uses an arrangement of localized phosphors to act as local light sources for a display. The phosphors are placed between two lens sheets. The lower lens sheet acts to focus light from a collimated backlight into the phosphors. The second lens sheet acts to focus light emitted by a phosphor though a selected TFT aperture of an LCD panel. The phosphor and dual lens-array assembly is separated from the main part of the display.
JP 2010066437 (O. Ito et al.; published Mar. 25, 2010) describes a display in which an arrangement of localized phosphors is placed above an LC panel and a collimated backlight. Light from the collimated backlight is focused through the TFT apertures of the display panel and into the correctly indexed phosphor region. This arrangement is subject to unwanted phosphor excitation by ambient light. Some ambient light also reflects in the chambers that house the phosphors. These aspects can lower the contrast of the display unless viewed in a darkened environment.
WO 2004/099664 (T. Jüstel; published November 2004) describes a phosphor on a lightguide which may be excited from rays leaking from the lightguide. The publication does not cover pixilated arrangements appropriate for making a display.
U.S. Pat. No. 7,339,638 (K. Kitamura; published Apr. 13, 2006) uses a dual lens layer, each layer containing lenses near every LC pixel. Colours are separated by angle and pass through the LC. This system is more suited to a projector than a display.
U.S. Pat. No. 5,146,355 (J. Prince et al.; published Sep. 8, 1992) describes an arrangement of phosphors situated below an LC panel. A transflective configuration is described.
U.S. Pat. No. 6,864,626 B1 (S. Weiss et al.; published Mar. 8, 2005) describes display configurations involving optically pumped luminescent nanocrystals.
U.S. Pat. No. 5,608,554 (Y. Do et al.; published Mar. 4, 1997) describes an LCD which contains a phosphor layer and a backlight source with a main emitting peak in the region 380-420 nm. The phosphor distribution resides on the opposite side of the LC layer from the backlight.
U.S. Pat. No. 6,473,144 (N. Ichikawa et al., published Oct. 29, 2002) and US 2007/0047221 (S. Park; published Mar. 1, 2007) use a holographic array or diffractive gratings to separate colours and focus them onto separate pixels. This approach is technically demanding and expensive to implement.